Tired of loading it to travel . Have farms scattered 90 miles. 25 miles east of Billings & 50& south west. When I bought the machine I was 125 miles with a 100 mile haul. Needed tracks for the seep in Wyoming . Never had to "halter break " the machine, but a lot of places a empty grain cart & tractor could not follow.  With tires I will road it the 50 miles & maybe haul it home 75 miles.  IF I had pull outs on the rgn I might stay with tracks, but I'm not going to buy a $40-50,000 rgn for 2 uses a yr. 
Love the tracks in the field. But too much road work.  I can drop $30000 rebuilding the tracks, or spend $15000 going tires.  will store the tracks for a " just in case" year